CN206490868U - Led driver - Google Patents

Led driver Download PDF

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Publication number
CN206490868U
CN206490868U CN201720131633.5U CN201720131633U CN206490868U CN 206490868 U CN206490868 U CN 206490868U CN 201720131633 U CN201720131633 U CN 201720131633U CN 206490868 U CN206490868 U CN 206490868U
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Prior art keywords
circuit
led driver
pin
voltage
type triode
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吴孝军
王海军
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Zhejiang Yingfeite Optoelectronics Co Ltd
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Zhejiang Yingfeite Optoelectronics Co Ltd
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    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/30—Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

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  • Circuit Arrangement For Electric Light Sources In General (AREA)

Abstract

This application discloses a kind of LED driver; its output parameter changes with the electrical parameter of one of pin P1 of main control chip in main circuit, in addition, the LED driver also includes under-voltage protecting circuit; the under-voltage protecting circuit specifically includes acquisition circuit and adjustment circuit, wherein：The main circuit and adjustment circuit of circuit connection LED driver are obtained, the value of LED driver input voltage size is characterized for obtaining, and export to adjustment circuit；The output end of adjustment circuit connects the pin P1, for the value of the sign LED driver input voltage size to be adjusted into the electrical parameter that the pin P1 can be recognized, and export to the pin P1, to cause the electrical parameter of the pin P1 corresponding with the value of the sign LED driver input voltage size；The main control chip is when the electrical parameter of the pin P1 enters default value interval, and control LED driver drop volume runs or shut down, and can realize under-voltage protection.

Description

LED driver
Technical field
The utility model is related to electric and electronic technical field, more specifically to LED driver.
Background technology
The input connection power network of LED (Light Emitting Diode, light fly-wheel diode) driver, output end LED is connected, for line voltage to be converted into the electrical parameter of LED needs to drive LED to light.Work as voltage ripple of power network And when there is under-voltage (i.e. grid voltage amplitude is less than the minimum input voltage amplitude that LED driver is identified), it is easily caused LED drives Dynamic device is damaged.
Utility model content
In view of this, the utility model provides a kind of LED driver, can realize under-voltage protection.
A kind of LED driver, its output parameter becomes with the electrical parameter of one of pin P1 of main control chip in main circuit Change, in addition, the LED driver also includes under-voltage protecting circuit, the under-voltage protecting circuit specifically includes acquisition circuit and tune Whole circuit, wherein：
The main circuit and the adjustment circuit for obtaining circuit connection LED driver, LED driver is characterized for obtaining The value of input voltage size, and export to the adjustment circuit；
The output end of the adjustment circuit connects the pin P1, for the sign LED driver input voltage is big Small value is adjusted to the electrical parameter that the pin P1 can be recognized, and exports to the pin P1, to cause the pin P1's Electrical parameter is corresponding with the value of the sign LED driver input voltage size；
The main control chip is when the electrical parameter of the pin P1 enters default value interval, control LED driver drop volume Operation is shut down.
Wherein, the pin P1 is the protection pin of the main control chip.
Wherein, the acquisition circuit is peak holding circuit.
Wherein, the peak holding circuit includes diode and electric capacity, specifically：
Rectifier bridge and filter capacitor are included in the main circuit of LED driver, the filter capacitor is connected to the rectifier bridge Output end；
The anode of the diode connects the positive output end of the rectifier bridge, the negative output terminal ground connection of the rectifier bridge；
The negative electrode of the diode is through the capacity earth；
The negative electrode of the diode accesses the adjustment circuit as the output end of the peak holding circuit.
Wherein, the adjustment circuit is linear regulation circuit.
Wherein, the linear regulation circuit includes first resistor, second resistance, operational amplifier and the pole of the first NPN type three Pipe, specifically：
The output end for obtaining circuit is grounded through the first resistor and the second resistance；
The inverting input of the operational amplifier connects the intermediate node of the first resistor and the second resistance, its Homophase input terminates the colelctor electrode and the pin P1 of first NPN type triode, and it exports termination first NPN type three The base stage of pole pipe；
The grounded emitter of first NPN type triode.
Wherein, the adjustment circuit includes comparison circuit and execution circuit, specifically：
The input of the comparison circuit connection output end and the execution circuit for obtaining circuit, for described When the value for characterizing LED driver input voltage size is equal to or less than reference voltage, produces control signal and issue and described perform electricity Road；
The execution circuit drags down the pin P1 current potentials after the control signal is received, and the main control chip exists Control LED driver shutdown when the pin P1 is low level.
Wherein, the comparison circuit includes 3rd resistor, the 4th resistance and comparator, and the execution circuit includes the 5th electricity Resistance, the first NPN type triode and the first PNP type triode, specifically：
The output end for obtaining circuit is through the 3rd resistor and the 4th resistance eutral grounding；
The signal input part of the voltage comparator connects the 3rd resistor and the intermediate node of the 4th resistance；
The base stage of output termination first PNP type triode of the voltage comparator；
The emitter stage of first PNP type triode connects power supply；
The colelctor electrode of first PNP type triode is through the 5th resistance eutral grounding, while connecing the pole of the first NPN type three The base stage of pipe；
The colelctor electrode of first NPN type triode meets the pin P1, grounded emitter.
Wherein, the adjustment circuit includes linear regulation circuit, comparison circuit and execution circuit, specifically：
The linear regulation circuit connection output end and the pin P1 for obtaining circuit, the main control chip is with institute State the decline control LED driver drop volume operation of pin P1 current potentials；
The input of the comparison circuit connection output end and the execution circuit for obtaining circuit, for described When the value for characterizing LED driver input voltage size is equal to or less than reference voltage, produces control signal and issue and described perform electricity Road；The execution circuit drags down the pin P1 current potentials after the control signal is received, and the main control chip is described Control LED driver shutdown when pin P1 is low level.
Alternatively, the LED driver also includes：Overvoltage crowbar, for when LED driver input voltage is over-pressed The pin P1 current potentials are dragged down, main control chip control LED driver shutdown when the pin P1 is low level.
It can be seen from above-mentioned technical scheme that, the utility model is using can be according to pin P1 electrical parameter VpChange, Control LED driver switches to the chip that drop volume runs or shut down as the main control chip of LED driver by rated power operation IC, while the utility model will be with LED driver input voltage VinThe corresponding value of size is reflected to pin P1 in real time, then only V when needing setting LED driver input voltage under-voltageinSize and pin P1 main control chips IC control LED driver drop volume fortune V when row or shutdownpSize is corresponding, it is possible to make it defeated in LED driver by the control functions of main control chip IC in itself The drop volume operation of control LED driver or shutdown, so as to avoid the under-voltage operation of LED driver, are realized deficient when entering under-voltage Pressure protection.
Brief description of the drawings
, below will be to embodiment in order to illustrate more clearly of the utility model embodiment or technical scheme of the prior art Or the accompanying drawing used required in description of the prior art is briefly described, it should be apparent that, drawings in the following description are only It is some embodiments of the present utility model, for those of ordinary skill in the art, is not paying the premise of creative work Under, other accompanying drawings can also be obtained according to these accompanying drawings.
Fig. 1 is a kind of LED driver structural representation disclosed in the utility model embodiment；
Fig. 2 is the output current I of LED driver shown in Fig. 1oWith pin P1 electrical parameter VpVariation relation figure；
Fig. 3, which is shown, obtains circuit and the structural representation of adjustment circuit in LED driver shown in Fig. 1；
Fig. 4, which is shown, obtains circuit and the another structural representation of adjustment circuit in LED driver shown in Fig. 1；
Fig. 5 is the topological structure schematic diagram of adjustment circuit shown in Fig. 4；
Fig. 6 is another LED driver structural representation disclosed in the utility model embodiment.
Embodiment
Below in conjunction with the accompanying drawing in the utility model embodiment, the technical scheme in the utility model embodiment is carried out Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of the utility model, rather than whole Embodiment.Based on the embodiment in the utility model, those of ordinary skill in the art are not under the premise of creative work is made The every other embodiment obtained, belongs to the scope of the utility model protection.
Referring to Fig. 1, the utility model embodiment discloses a kind of LED driver, can realize under-voltage protection.The LED The building block of driver includes main circuit and under-voltage protecting circuit, and the under-voltage protecting circuit specifically includes acquisition circuit 100 With adjustment circuit 200, wherein：
The output parameter of LED driver with main control chip IC one of pin P1 in main circuit electrical parameter VpBecome Change, specifically, electrical parameter Vs of the main control chip IC in pin P1pDuring into default value interval, control LED driver drop volume fortune Row shuts down, and this is the principle for needing to follow in main control chip IC type selectings and pin selection；
The main circuit and adjustment circuit 200 of the connection LED driver of circuit 100 are obtained, it is defeated for obtaining sign LED driver Enter voltage VinThe value of size, and export to adjustment circuit 200；
The output end connection pin P1 of adjustment circuit 200, for by the sign LED driver input voltage received VinThe value of size is adjusted to the electrical parameter V that pin P1 can be recognizedp(electrical parameter can be voltage signal or electricity Signal is flowed, is not limited to；The electrical parameter V that pin P1 can be recognizedp, refer to electrical parameter VpType and size be input to pin P1 Afterwards, main control chip IC will not be damaged, and the main circuit output parameter of LED driver can be made to follow VpChange.), and export Pin P1 is given, to cause pin P1 electrical parameter VpWith the sign LED driver input voltage VinThe value of size is corresponding.
Seen from the above description, the present embodiment is using can be according to pin P1 electrical parameter VpChange, controls LED driver The chip that drop volume runs or shut down is switched to as the main control chip IC of LED driver by rated power operation, while this implementation Example will be with LED driver input voltage VinThe corresponding value of size is reflected to pin P1 in real time, then only need to setting LED drivings V when device input voltage is under-voltageinV when size controls LED driver drop volume operation or shut down with pin P1 main control chips ICpGreatly It is small corresponding, it is possible to it is controlled when LED driver input voltage is under-voltage by the control functions of main control chip IC in itself LED driver drop volume operation is shut down, so as to avoid the under-voltage operation of LED driver, realizes under-voltage protection.
Wherein, pin P1 can use main control chip IC protection pin, such as overheat protector pin, under-voltage protection pin, but simultaneously Do not limit to.
For the main control chip IC of a certain model, when pin P1 is the overheat protector pin of master control chip IC, LED driver Output current IoWith pin P1 electrical parameter VpVariation relation, as shown in Figure 2：Vp＞ VTF(start)When, IoIt is constantly equal to LED drives Dynamic device output-current rating value；Vp≤VTF(start)Belong to the under-voltage stage；VTF(stop)<Vp≤VTF(start)When, VpWith IoIt is directly proportional； VOTF(off)<Vp≤VTF(stop)For between stagnant ring region；Vp≤VOTF(off)When, LED driver shutdown.Based on this, by setting LED drivings Correspondence V when device input voltage is under-voltagep≤VTF(start)State, then by VTF(stop)<Vp≤VTF(start)When control LED driving Device drop volume operation, and/or in Vp≤VOTF(off)When control LED driver shutdown, you can realize LED driver in whole under-voltage rank Under-voltage protection function under section or part under-voltage stage.
For ease of description, it will be used for realizing " in VTF(stop)<Vp≤VTF(start)When control LED driver drop volume operation " Under-voltage protecting circuit is defined as under-voltage drop volume circuit, will be used for realizing " in Vp≤VOTF(off)When control LED driver shutdown " Under-voltage protecting circuit is defined as under-voltage shutdown circuit.Under-voltage drop volume circuit and under-voltage shutdown circuit can be used alone to be driven in LED To realize under-voltage protection function of the LED driver under the under-voltage stage of part in dynamic device, it can also apply simultaneously in LED driver In to realize under-voltage protection function of the LED driver under the whole under-voltage stage.
Either in under-voltage drop volume circuit or in under-voltage shutdown circuit, the preferred peak holding circuit of circuit 100 is obtained. The effect of peak holding circuit is to obtain LED driver input voltage VinPeak value VinmaxAnd kept for a period of time, it exports electricity Press as stable DC voltage.Compared to other kinds of acquisition circuit 100, such as RC circuits, peak holding circuit output signal More steady, ripple is smaller, thus sampling precision is higher.
Peak holding circuit can use topological structure as shown in Figure 3, but not limit to.Peak holding circuit bag shown in Fig. 3 Diode D1 and electric capacity C1 are included, specifically：Rectifier bridge and filter capacitor C2, filter capacitor are included in the main circuit of LED driver C2 is connected to the output end of the rectifier bridge；Diode D1 anode connects the positive output end of the rectifier bridge, the rectifier bridge Negative output terminal is grounded；Diode D1 negative electrode is grounded through electric capacity C1；Diode D1 negative electrode is used as the peak holding circuit Output end, accesses adjustment circuit 200.
In under-voltage drop volume circuit, the preferred linear regulation circuit of adjustment circuit 200.The effect of linear regulation circuit is docking The sign LED driver input voltage V receivedinThe value of size makees linear process, obtains the electricity ginseng that pin P1 can be recognized Number Vp, and export and give pin P1.
The topological structure of linear regulation circuit refers to Fig. 3, including first resistor R1, second resistance R2, operational amplifier U1 and the first NPN type triode Q1, specifically：The output end for obtaining circuit 100 is grounded through first resistor R1 and second resistance R2； Operational amplifier U1 inverting input connection first resistor R1 and second resistance R2 intermediate node, its homophase input termination the One NPN type triode Q1 colelctor electrode and pin P1, it exports the first NPN type triode Q1 of termination base stage；First NPN type three Pole pipe Q1 grounded emitter.
The operation principle of circuit shown in Fig. 3 is as follows：LED driver input voltage VinInput after the peak holding circuit, Voltage V on electric capacity C1c1=Vinmax, the voltage V1=V of operational amplifier U1 reverse input endsc*R1/(R2+R1)；Assuming that LED Driver normal input voltage is 170V~240V, and is required in LED driver input voltage in the slight of 110V~170V Downrating during under-voltage condition, then can be set 170V<Vin<Correspondence V during 240Vp＞ VTF(start)State, while set 110V <VinCorrespondence V during≤170VTF(stop)<Vp≤VTF(start)State, then：Work as 170V<Vin<During 240V, LED driver output Load current value；Work as 110V<VinDuring≤170V, VinIncrease so that Vc1Increase, and then cause V1 increases, and V1 increases can make fortune Calculate amplifier U1 output voltages to reduce, and then cause the first NPN type triode Q1 collector voltage (namely Vp) increase, so It is achieved that in 110V<VinIn≤170V, VpWith VinProportional change, then LED driver output current IoWith VinIt is proportional to become Change, main control chip IC is run with the decline control LED driver drop volume of pin P1 current potentials.
In under-voltage shutdown circuit, adjustment circuit 200 includes comparison circuit 201 and execution circuit 202, as shown in figure 4, than The input of the output end with execution circuit 202 that obtain circuit 100 is connected compared with circuit 201, in the sign LED driver Input voltage VinWhen the value of size is equal to or less than reference voltage, produces control signal and issue execution circuit 202, execution circuit 202 drag down pin P1 current potentials after the control signal is received, and main control chip IC controls LED when pin P1 is low level Driver shuts down.
Comparison circuit 201 and the topological structure of execution circuit 202 refer to Fig. 5.In Figure 5, comparison circuit 201 includes the Three resistance R3, the 4th resistance R4 and comparator U2, execution circuit 202 include the 5th resistance R5, the first NPN type triode Q1 and the One PNP type triode Q2, wherein：
The output end for obtaining circuit 100 is grounded through 3rd resistor R3 and the 4th resistance R4；
Voltage comparator U2 signal input part connects 3rd resistor R3 and the 4th resistance R4 intermediate node；
Voltage comparator U2 the first PNP type triode Q2 of output termination base stage；
First PNP type triode Q2 emitter stage meets power supply VCC；
First PNP type triode Q2 colelctor electrode is grounded through the 5th resistance R5, while connecing the first NPN type triode Q1 base Pole；
First NPN type triode Q1 colelctor electrode meets pin P1, grounded emitter.
Fig. 5 operation principle is as follows：As input voltage VinEqual to or less than under-voltage shutdown threshold voltage when, the electricity on R4 Pressure is equal to or less than reference voltage V ref, and voltage comparator U2 output low levels, Q2 is turned on, and Q2 collector voltage is high electricity Flat, Q1 conductings, pin P1 voltage is pulled low, LED driver shutdown.As input voltage VinHigher than the threshold voltage of under-voltage shutdown When, voltage comparator U2 output high level, Q2 cut-offs, Q2 collector voltage is low level, and Q1 cut-offs will not be to pin P1's Voltage is impacted.
Wherein, when circuit shown in Fig. 3 and Fig. 5 is applied in LED driver simultaneously, the Q1 in Q1 and Fig. 5 in Fig. 3 is Same device.
Alternatively, any LED driver disclosed above also includes：Overvoltage crowbar, for defeated in LED driver The pin P1 current potentials are dragged down when entering electric voltage over press, main control chip control LED when the pin P1 is low level drives Dynamic device shutdown.As shown in fig. 6, the boosting protection circuit includes the 6th resistance R6, the 7th resistance R7, the 8th resistance R8, the 9th Resistance R9, the second NPN type triode Q3, the second PNP type triode Q4 and NMOS tube Q5, wherein：
6th resistance R6 is connected in parallel on the output end of rectifier bridge in the main circuit of LED driver again after being connected with the 7th resistance R7 (or, the 6th resistance R6 is connected in parallel on the output end that circuit 100 is obtained in under-voltage protecting circuit again after being connected with the 7th resistance R7, Under-voltage protecting circuit is not shown in figure 6)；
Second NPN type triode Q3 base stage connects the 6th resistance R6 and the 7th resistance R7 intermediate node；
Second NPN type triode Q3 grounded emitter；
Second NPN type triode Q3 colelctor electrode connects the second PNP type triode Q4 base stage, while being connect through the 8th resistance R8 Power supply VCC；
Second PNP type triode Q4 colelctor electrode is grounded through the 9th resistance R9, while connecing NMOS tube Q5 grid；
Second PNP type triode Q4 emitter stage meets power supply VCC；
NMOS tube Q5 source ground, drain electrode meets pin P1.
The operation principle of boosting protection circuit shown in Fig. 6 is as follows：When input voltage is over-pressed, Q3 conductings, Q4 conductings, Q5 grid Pole tension is high level, and Q5 conductings, pin P1 voltages are pulled low, LED driver shutdown.
In summary, the utility model is using can be according to pin P1 electrical parameter VpChange, control LED driver is by volume The main control chip IC that Power operation switches to the chip that drop volume runs or shut down as LED driver is determined, while the utility model Will be with LED driver input voltage VinThe corresponding value of size is reflected to pin P1 in real time, then only need to set LED driver V when input voltage is under-voltageinV when size controls LED driver drop volume operation or shut down with pin P1 main control chips ICpSize It is corresponding, it is possible to it is controlled LED when LED driver input voltage is under-voltage by the control functions of main control chip IC in itself Driver drop volume operation is shut down, so as to avoid the under-voltage operation of LED driver, realizes under-voltage protection.
The embodiment of each in this specification is described by the way of progressive, and what each embodiment was stressed is and other Between the difference of embodiment, each embodiment identical similar portion mutually referring to.
The foregoing description of the disclosed embodiments, enables professional and technical personnel in the field to realize or new using this practicality Type.A variety of modifications to these embodiments will be apparent for those skilled in the art, determine herein The General Principle of justice can in other embodiments be realized in the case where not departing from spirit or scope of the present utility model.Cause This, the utility model is not intended to be limited to the embodiments shown herein, and is to fit to and principles disclosed herein The most wide scope consistent with features of novelty.

Claims (10)

1. a kind of LED driver, its output parameter changes with the electrical parameter of one of pin P1 of main control chip in main circuit, Characterized in that, the LED driver also include under-voltage protecting circuit, the under-voltage protecting circuit specifically include acquisition circuit and Adjustment circuit, wherein：
The main circuit and the adjustment circuit for obtaining circuit connection LED driver, LED driver input is characterized for obtaining The value of voltage swing, and export to the adjustment circuit；
The output end of the adjustment circuit connects the pin P1, for by the sign LED driver input voltage size Value is adjusted to the electrical parameter that the pin P1 can be recognized, and exports to the pin P1, to cause the electricity of the pin P1 to join Number is corresponding with the value of the sign LED driver input voltage size；
The main control chip is when the electrical parameter of the pin P1 enters default value interval, control LED driver drop volume operation Or shutdown.
2. LED driver according to claim 1, it is characterised in that the pin P1 is the protection of the main control chip Pin.
3. LED driver according to claim 1, it is characterised in that the acquisition circuit is peak holding circuit.
4. LED driver according to claim 3, it is characterised in that the peak holding circuit includes diode and electricity Hold, specifically：
Rectifier bridge and filter capacitor are included in the main circuit of LED driver, the filter capacitor is connected to the defeated of the rectifier bridge Go out end；
The anode of the diode connects the positive output end of the rectifier bridge, the negative output terminal ground connection of the rectifier bridge；
The negative electrode of the diode is through the capacity earth；
The negative electrode of the diode accesses the adjustment circuit as the output end of the peak holding circuit.
5. LED driver according to claim 1, it is characterised in that the adjustment circuit is linear regulation circuit.
6. LED driver according to claim 5, it is characterised in that the linear regulation circuit includes first resistor, the Two resistance, operational amplifier and the first NPN type triode, wherein：
The output end for obtaining circuit is grounded through the first resistor and the second resistance；
The inverting input of the operational amplifier connects the intermediate node of the first resistor and the second resistance, its same phase The colelctor electrode and the pin P1 of input termination first NPN type triode, it exports termination first NPN type triode Base stage；
The grounded emitter of first NPN type triode.
7. LED driver according to claim 1, it is characterised in that the adjustment circuit includes comparison circuit and execution Circuit, wherein：
The input of the comparison circuit connection output end and the execution circuit for obtaining circuit, for being characterized described When the value of LED driver input voltage size is equal to or less than reference voltage, produces control signal and issue the execution circuit；
The execution circuit drags down the pin P1 current potentials after the control signal is received, and the main control chip is described Control LED driver shutdown when pin P1 is low level.
8. LED driver according to claim 7, it is characterised in that the comparison circuit includes 3rd resistor, the 4th electricity Resistance and comparator, the execution circuit include the 5th resistance, the first NPN type triode and the first PNP type triode, wherein：
The output end for obtaining circuit is through the 3rd resistor and the 4th resistance eutral grounding；
The signal input part of the voltage comparator connects the 3rd resistor and the intermediate node of the 4th resistance；
The base stage of output termination first PNP type triode of the voltage comparator；
The emitter stage of first PNP type triode connects power supply；
The colelctor electrode of first PNP type triode is through the 5th resistance eutral grounding, while connecing first NPN type triode Base stage；
The colelctor electrode of first NPN type triode meets the pin P1, grounded emitter.
9. LED driver according to claim 1, it is characterised in that the adjustment circuit includes linear regulation circuit, ratio Compared with circuit and execution circuit, wherein：
The linear regulation circuit connection output end and the pin P1 for obtaining circuit, the main control chip draws with described The decline control LED driver drop volume operation of pin P1 current potentials；
The input of the comparison circuit connection output end and the execution circuit for obtaining circuit, for being characterized described When the value of LED driver input voltage size is equal to or less than reference voltage, produces control signal and issue the execution circuit；Institute State execution circuit to drag down the pin P1 current potentials after the control signal is received, the main control chip is in the pin P1 LED driver shutdown is controlled during for low level.
10. LED driver according to claim 1, it is characterised in that the LED driver also includes：Overvoltage protection electricity Road, for dragging down the pin P1 current potentials when LED driver input voltage is over-pressed, the main control chip is in the pin P1 LED driver shutdown is controlled during for low level.
CN201720131633.5U 2017-02-14 2017-02-14 Led driver Active CN206490868U (en)

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Application Number Priority Date Filing Date Title
CN201720131633.5U CN206490868U (en) 2017-02-14 2017-02-14 Led driver

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201720131633.5U CN206490868U (en) 2017-02-14 2017-02-14 Led driver

Publications (1)

Publication Number Publication Date
CN206490868U true CN206490868U (en) 2017-09-12

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Country Status (1)

Country Link
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